1. The Field of the Invention
The present invention broadly relates to apparatus for treating water. In one of its more specific embodiments, the invention is concerned with an improved apparatus for treating waste water with a chemical. The apparatus is especially useful in treating acidic mine water with a chemical having a basic reaction to thereby neutralize or partially neutralize the same before discharge into a stream or sewer.
2. The Prior Art
Acid mine water, aqueous industrial acid wastes and other acidic waste water streams constitute a long standing water pollution problem. Fish and other forms of aquatic life are killed when substantial amounts of acid wastes of these types are discharged directly into streams, lakes and ponds without prior treatment. Esthetic and recreational values are also damaged as often the resultant polluted water is discolored, has unpleasant odors, and is not suitable in general for swimming, boating, fishing and other recreational pursuits.
As a result of the foregoing, most localities have enacted strict water pollution statutes which are enforced very vigorously. One of the usual requirements is that the acid waste water be neutralized by treatment with a suitable alkaline substance prior to discharge. Examples of chemicals commonly added to acid waste water for neutralization purposes include hydrated lime, soda ash and particulate limestone.
The apparatus available heretofore for neutralizing acid waste water has not been entirely satisfactory for a number of reasons. As a general rule, the prior art apparatus required an outside power source and a full time operator which markedly increased the operating costs. Often the prior art apparatus was not capable of automatic or semi-automatic operation, and it was not possible to effectively control the amount of neutralizing chemical that was added per unit volume of treated water. Also, the apparatus was not self-contained in most instances, and it could not be moved easily from site to site for use on a permanent, semi-permanent or temporary basis.
As a result of the foregoing and other deficiencies and disadvantages, the art has long sought without success an entirely satisfactory apparatus for treating water with a chemical. However, apparatus that was entirely satisfactory in all respects was not available prior to the present invention.